The ancient Egyptians relied upon the solar-stellar calendar. Mesopotamian civilization had more faith on the zodiacal house-lunar astronomy/astrology. The records of transition from solar-stellar to lunar-stellar astronomy/astrology among the Aryans are lost. During the formative years of Vedic lunar-stellar astronomy, which may be any

time before 2500 B.C., the first indirect reference to lunar-stellar astronomy is found in the verse which states that Daksha (son of Prajapati Brahma, the creator) got his 27 daughters married to the Moon, of which 7 were Kritikas. The name Kritika signifies that this verse is about charting the passage of the Moon, where probably 33 Naksatra were used. According to S.D. Sharma (Pre Vedanga astronomy. P. 135) initially only 24 Naksatras were considered to be sufficient to chalk the progress of the Moon through the maze of stars. At the stage there was no attempt to synchronize the movement of the Moon from one Naksatra to next with the length of time forming a terrestrial day (S.D. Sharma. Opp.cit). The 24 Naksatra (stellar constellations) were identified by their yogatarakas (identifying stars) and at a slightly later age the Naksatras also started representing angular spaces (distance) on the lunar path.

In the second stage of advancement, attempts were made to demarcate 'day by day' progress of the Moon. The job was not found to be an easy one as the Moon's motion is not of uniform speed. Within a time span of one terrestrial day the Moon may cover from 11º to 15 º 30' of angular space. To surmount this problem, the lunar path was broken into different 'section', each section having 15, 30, or 45 muhuratas, depending upon on which part of the lunar passage that section is located. Each muhuratas had about 48 minutes time span (S.D. Sharma. opp. at. P. 142).

These intricate adjustments were done by different schools astrology/astronomy recognized by the name of their initiators, as Rishi Grtsamada, Vishvamitra, Vamadeva, Atri, Varadwaja, Vasistha, Garga, Dhruba, Narada etc. The last four among them definitely had knowledge of alien astrology/astronomy originating in Mesopotamia. During this 1500 to 2000 years long operation (S.D. Sharma puts the age of Lagadha as 1400 B.C.; about 600 yrs ahead of other scholars) the name of the Naksatras were frequently changed; stars were added and subtracted from individual Naksatras; 'Tarakas' were related among the established Naksatras. All these fervent activities evince that there was a conscious attempt to synchronize the progress of the Moon from Nakstra to Naksatra with the time length of a terrestrial day. The stars were added or subtracted to lengthen or shorten the angular space and the cumulative result was total chaos. Risi Lagadha removed the confusion in one stroke by allotting each of the 27 Naksatra equal angular space (the period is guessed variously from1400 B. C. to 800 B. C.) H. Yajnik (Vedanga Jyotisha. Hind. P. 57) showed that the replacement of solar -stellar astronomy by the lunar stellar astronomy was completed by the time of Yajusha Jyotisha, but its period of commencement is not known.

Not did everybody accept the Lagadha's solution. Maitrai Samhita did not abandon the 28th Naksatra, nor did the post-Vedic works of Parasara and Surya Siddhanta.

Even in modern Indian astrology dissention is still there, and it is not yet settled whether 28 Naksatras or 27 Naksatras with JAVADI correction yields better 'predictive results'.